A new study from Université Laval in Quebec City is sorry to report, however, that it isn’t true — and even warns that holding onto these beliefs can “cloud clinical judgment.”

They came upon this finding almost by accident. During a three-year study tracking panic attacks in people who entered two Quebec emergency rooms with unexplained chest pains, researchers were inspired by staff to see if lunar cycles did, in fact, line up with higher rates of people with mental illness coming in for care.

“While we were there, we were speaking with the staff and people were saying things like ‘Oh you know today’s the full moon, you’re going to have a lot of participants for your study,’” said lead study author Genevieve Belleville, a psychologist and professor of psychology at Université Laval where she researches anxiety and sleep disorders, adding that the staff inspired the side research project.

While the full moon comments could be taken as mere workplace banter, Ms. Belleville said she thinks “it’s anchored in a true belief.”

“And we just said ‘OK we’ve got the data, we’ll check it out,’” she said. “But we didn’t find any links.”

As they carried out their primary study on 771 participants, Ms. Belleville and her colleague Guillaume Foldes-Busque, who is affiliated with Université du Québec à Montréal, also kept track of the 34 to 37 lunar cycles during that time-frame and analyzed whether there was a higher incidence of panic attacks in the ER on dates when there was a full moon. The side study also set out to determine whether the seasons had any effect on rates of panic attacks in the emergency rooms at Sacré-Coeur Hospital in Montreal and Université Laval-affiliated hospital Hôtel-Dieu de Lévis.

There were seasonal impacts: panic was more frequently encountered in the spring and anxiety disorders in the summer, which surprised the authors, who expected to see more in winter and fall when seasonal affective disorder is known to happen.

“No significant impacts of lunar cycles were observed on panic, anxiety and mood disorders, or suicide ideation,” the study results read. “There was one exception: anxiety disorders other than panic disorders were 32% less frequent during the last quarter [of the lunar cycle],” a result Ms. Belleville just chalks up to a statistical blip.

No significant impacts of lunar cycles were observed on panic, anxiety and mood disorders, or suicide ideation

In its conclusion, the study urged emergency room professionals to “abandon their beliefs about the influence of lunar cycles on the mental health of their patients.

“Such unfounded beliefs could cloud their clinical judgment in critical situations and should not be upheld in a professional environment such as the [emergency department],” the study read.

Still, she said she’s already heard from others in the medical profession who maintain their belief and challenge her and her colleagues to do more research that may find there really is something to the full-moon effect.

Some are suggesting she analyze 911 calls and police reports on full moon nights to see if there is an uptick.

“Maybe with the help of some interested students we can pursue that,” she said.